Basic: import IntrusiveRefCntPtr<> into clang namespace

The class name is long enough without the llvm:: added.
Also bring in RefCountedBase and RefCountedBaseVPTR.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@150958 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/arcmt-test/arcmt-test.cpp b/tools/arcmt-test/arcmt-test.cpp
index 0ac7837..881a058 100644
--- a/tools/arcmt-test/arcmt-test.cpp
+++ b/tools/arcmt-test/arcmt-test.cpp
@@ -107,8 +107,8 @@
                               ArrayRef<const char *> Args) {
   DiagnosticConsumer *DiagClient =
     new TextDiagnosticPrinter(llvm::errs(), DiagnosticOptions());
-  llvm::IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
-  llvm::IntrusiveRefCntPtr<DiagnosticsEngine> Diags(
+  IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
+  IntrusiveRefCntPtr<DiagnosticsEngine> Diags(
       new DiagnosticsEngine(DiagID, DiagClient));
   // Chain in -verify checker, if requested.
   VerifyDiagnosticConsumer *verifyDiag = 0;
@@ -153,8 +153,8 @@
 
   DiagnosticConsumer *DiagClient =
     new TextDiagnosticPrinter(llvm::errs(), DiagnosticOptions());
-  llvm::IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
-  llvm::IntrusiveRefCntPtr<DiagnosticsEngine> TopDiags(
+  IntrusiveRefCntPtr<DiagnosticIDs> DiagID(new DiagnosticIDs());
+  IntrusiveRefCntPtr<DiagnosticsEngine> TopDiags(
       new DiagnosticsEngine(DiagID, DiagClient));
 
   CompilerInvocation origCI;